ABSTRACT
A penicillin-binding protein of molecular weight 76,000 inducible by beta-lactams was detected in methicillin-resistant Staphylococcus haemolyticus and Staphylococcus simulans. DNA from these strains hybridized to the mecA gene from Staphylococcus aureus; however, the chromosomal HindIII fragments containing the mecA genes were 3.4 kilobases in S. haemolyticus and 4.3 kilobases in S. simulans.
Subject(s)
Bacterial Proteins , Genes, Bacterial , Hexosyltransferases , Methicillin/pharmacology , Penicillin Resistance , Peptidyl Transferases , Staphylococcus aureus/drug effects , Staphylococcus/drug effects , Blotting, Southern , Carrier Proteins/analysis , Carrier Proteins/isolation & purification , Culture Media , DNA, Bacterial/metabolism , Deoxyribonuclease HindIII/analysis , Electrophoresis, Polyacrylamide Gel , Gene Expression Regulation, Bacterial , Muramoylpentapeptide Carboxypeptidase/analysis , Muramoylpentapeptide Carboxypeptidase/isolation & purification , Nucleic Acid Hybridization , Penicillin-Binding Proteins , Restriction Mapping , Staining and Labeling , Staphylococcus/genetics , Staphylococcus aureus/geneticsABSTRACT
Chromosomal BamHI DNA fragments containing both the mecA gene encoding the penicillin-binding protein responsible for methicillin resistance and the aadD gene encoding 4',4"-adenylyltransferase responsible for tobramycin resistance were cloned from three methicillin- and tobramycin-resistant strains of Staphylococcus aureus and one strain of Staphylococcus epidermidis. Physical maps of the fragments were similar, suggesting their unique origin.
Subject(s)
DNA, Bacterial/genetics , Drug Resistance, Microbial/genetics , Methicillin/pharmacology , Staphylococcus/genetics , Tobramycin/pharmacology , Blotting, Southern , Chromosomes, Bacterial , Cloning, Molecular , Deoxyribonuclease BamHI/genetics , Deoxyribonuclease HindIII/genetics , Penicillin Resistance/genetics , Plasmids , Restriction Mapping , Staphylococcus/drug effects , Staphylococcus aureus/drug effects , Staphylococcus aureus/genetics , Staphylococcus epidermidis/drug effects , Staphylococcus epidermidis/geneticsABSTRACT
A beta-lactam-sensitive strain of Staphylococcus aureus could be converted to methicillin resistance by the introduction of a plasmid carrying the 4.3-kilobase HindIII chromosomal DNA fragment which encoded the mecA gene from a methicillin-resistant S. aureus. Transformant cells produced methicillin-resistant S. aureus-specific penicillin-binding protein constitutively, and additional insertion of an inducible penicillinase plasmid caused production of the pencillin-binding protein to become inducible.
